Typically, noise suppressors for noise suppression or noise filtering are provided to cables interconnecting electronic components together forming a system or apparatus. Various approaches have been proposed to hold and keep noise suppressors in position relative to the cable.
For example, JP-2007-317776-A proposes a flat cable holder including a lid and a noise suppressor holder (i.e., a ferrite core case) to hold the noise suppressor, such as a ferrite core. After wiring of the flat cable and setting of the ferrite core are completed, the lid is closed, thereby keeping the ferrite core in position relative to the flat cable.
Fixing the ferrite core relative to the flat cable, however, can entail the following inconvenience.
If the relative positions of the components interconnected by the flat cable are changed due to, for example, addition of an optional component, the cable route is changed. However, replacement of the cable is impractical because an end of the flat cable (i.e., connection to a connector) is generally disposed deep inside the apparatus. Although relay cables may be used, doing so requires a relay board as well, thus increasing the cost and size of the apparatus.
Therefore, even in a stripped-down apparatus without any optional components, the cable has a sufficient length to accommodate such an optional component, and flexible flat cables are widely used to attain higher flexibility in designing the cable route. Differences in the cable length inherent to the layout change can be absorbed relatively easily by slacking the flat cable.
Although this arrangement can eliminate the necessity of replacement of the flat cable, the direction of the portion where the noise suppressor is attached is fixed, and rigidity is added to portions of the cable adjacent to the entrance and the exit from the noise suppressor. Thus, the cable route around the noise suppressor is determined by the position and direction of the noise suppressor.
In conventional approaches, the ferrite core and the flat cable (flat harness) are fixed in a given route, and their positions are not changed even with changes in the cable route caused by the addition of optional components. Accordingly, the cable is unnecessarily long in the default setting because the cable length is increased to accommodate addition of the optional component. In this case, the cable is subjected to more noise, reliability can decrease, and the cost can increase.